The present invention relates to light intensifiers, particularly to devices for focusing down a beam of light to produce a smaller beam with a greater intensity, and more particularly to a lensing duct for intensifying light using a combination of front surface lensing and reflective waveguiding.
Traditionally, solid optically pumped lasers consist of a solid material wherein the optical gain in the material is generated by stimulated emission. The laser rod was initially optically pumped by a flash lamp or an arc source, which was generally inefficient and the heat generated by the pumping means sometimes damaged the laser rod.
In an effort to develop more efficient solid state lasers which generate higher output power and have a longer life time, the use of lateral pumping means, such as solid state laser diode arrays that are mounted on the side of a laser slab, was initiated. Various approaches for efficient transfer of the energy from the diode arrays to the solid laser rod or slab have been developed, which include the use of reflective coatings, optical waveguides, collimating lenses, and prisms.
One of the existing problems associated with the use of large diode arrays to pump lasing material is effectively concentrating the light from a diode array onto the laser slab or rod. The present invention provides a solution to that problem by condensing and increasing the intensity of pump light from a diode array onto a solid laser rod by a combination of front surface lensing and reflective waveguiding via a lensing duct constructed from inexpensive glass or plastic.